Towards a Structurally Based Constitutive Model of Urinary Bladder Wall Tissue Remodeling After Spinal Cord Injury

Spinal cord injury (SCI) is accompanied by urologic complications, characterized by two phases (early areflexic phase and late hyperreflexic phase), where the routine function of the urinary bladder of storing urine and voiding becomes compromised. In addition to functional deficiencies, these pathologies are often accompanied by changes in bladder wall tissue morphology and mechanical properties. Our experimental studies have revealed that the bladder wall can undergo rapid remodeling post-SCI (figs.1,2) and exhibits complex biomechanical responses (fig.2B) [1,2,3,4]. These remodeling events will result in profound changes in bladder wall biomechanical behavior (fig.2) and ultimately organ function. The specific alterations in mechanical behavior and functional properties of bladder wall tissue and the underlying mechanisms are not well understood. A multi-phase structural constitutive model of the bladder wall is clearly needed to understand how changes in various tissue components produce observed changes in bladder function.